Human Growth and Development
Learning Outcomes
Health: Part 1
Module 7 Content Guide
Human Growth and Development By the end of this module, you should be able to:
Describe the key phases that occur before birth.
Understand your place in the life cycle.
Key Concepts
Before Birth
Fertilization
Fertilization marks the beginning of the human life cycle.
Process of fertilization includes:
Some sperm are malformed and do not survive.
The vagina environment is not conducive to sperm survival until the right time for pregnancy arrives.
The cervix eventually allows for the entrance of sperm.
White blood cells may attack sperm, creating additional challenges for successful fertilization.
Sperm may get stuck in the fallopian tube, complicating their journey.
Only one sperm successfully fuses with the egg, leading to fertilization.
Pregnancy and Fetal Development
First Trimester:
The first twelve weeks of pregnancy.
At 16 weeks, the fetus is approximately the size of an avocado.
By 20 weeks, the fetus grows to around the length of a banana.
At 24 weeks, the fetus reaches almost a foot in length.
By 28 weeks, the fetus likely weighs over 2 pounds.
At 32 weeks, the fetus is just under 4 pounds.
By 36 weeks, the fetus weighs around 6 pounds.
By week 40, it is time for childbirth.
After Birth
Infancy and Childhood
Infancy starts from birth and lasts until the first two years of life.
By the end of the first two years, an average infant will be:
About 70% longer (taller) than at birth.
Weigh approximately 250% more than at birth.
Adolescence
Adolescence marks the transition from childhood to adulthood, initiated by the onset of puberty.
There are three types of key changes during adolescence:
a. Physical Changes
b. Emotional Changes
c. Social Changes
Adulthood
The legal age for adulthood is 18, but key brain development continues until around 25 years old.
Most changes during adulthood involve the adoption of new mindsets and habits rather than significant physical transformations.